I mean you can trace the toxic black and white angry culture, indirectly, to three main sources imo:
1) people imitating orgs like the Black Panthers, but not really having any direction, because they're milquetoast militants
2) offshoots of American Communist culture, a long-known toxic hellhole riddled with FBI moles deliberately causing schisms to destroy it
3) influential cause trolls, who found an angry disenfranchised population of angery adolescents